Grade 10

1st trimester

8201/7201

Development of the Modern Periodic Table

Mohamed Ahmed Abdelbari

Grade 10

trimester st1

1

Chemistry

Introduction Atom: the smallest, indivisible unit of an element that retains all chemical and physical

properties of the element.

For example, a single atom of gold has the same physical and chemical properties as

10 tons of gold. Atoms are composed of three subatomic particles.

subatomic particles: protons, neutrons, and electrons.

The Atom consists of: 1) The nucleus: A high-density region that is

present in the center of the atom and contains

protons of neutrons

a) Protons: particles that carry a positive

electrical charge and are present within the

nucleus of the atom

b) Neutrons: particles that do not carry an

electrical charge and are present inside the

nucleus of the atom

2) Electrons: particles that carry a negative charge and are found outside the nucleus

Electron cloud: The region where the

electrons are located around the nucleus.

Protons and electrons have opposite

charges and the number of protons in any

atom is equal to the number of electrons, so

the atom is electrically neutral.

Different atoms of elements: All the elements in nature are made up of atoms. The atoms of elements differ from one

another in the number of protons, neutrons and electrons

Atomic number: The number of protons in the nucleus of the atom of the element.

The nucleus of the hydrogen atom has 1 proton, so the atomic number of hydrogen is 1,

In the nucleus of the oxygen atom there are 8 protons so the atomic number of oxygen is 8

Mass number: The total number of protons and neutrons in the nucleus of the atom.

Electrons do not enter in the calculation of the mass number because the mass is too

small and can be neglected.

Grade 10

trimester st1

2

Chemistry

Classify the next materials (Element, Compound)

kind matter kind matter

E Sodium C Carbon dioxide

C Sulfur oxide III E Hydrogen

E Potassium C Sodium bicarbonate

E Oxygen C Zink sulfate

C Hydrochloric acid E Helium

E Aluminum C Iron chloride III

C Ammonium Nitrate E Carbon

Complete the next Table

# neutrons

# Electrons

# protons

Atomic mass

Atomic no. Element

4 3 3 7 3 𝑳𝒊𝟕𝟑

8 8 8 16 8 𝑶𝟏𝟔𝟖

18 17 17 35 17 𝑪𝒍𝟑𝟓𝟏𝟕

61 47 47 108 47 𝑨𝒈𝟏𝟎𝟖𝟒𝟕

10 10 10 20 10 𝑵𝒆𝟐𝟎𝟏𝟎

10 9 9 19 9 𝑭𝟏𝟗𝟗

Grade 10

trimester st1

3

Chemistry

Complete the Electron configuration of each element:

𝐂𝟏𝟐𝟔 𝐁𝟏𝟏

𝟓 𝐁𝐞𝟗𝟒 𝐋𝐢𝟕

𝟑 Element

6 5 4 3 # Electrons

electron configuration

2 , 1

# Valence electrons

𝐀𝐫𝟒𝟎𝟏𝟖 𝐂𝐥𝟑𝟓

𝟏𝟕 𝐀𝐥𝟐𝟕𝟏𝟑 𝐍𝐚𝟐𝟑

𝟏𝟏 Element # Electrons

electron configuration

# Valence

electrons

𝐁𝐫𝟖𝟎𝟑𝟓 𝐒𝐞𝟕𝟗

𝟑𝟒 𝐂𝐚𝟒𝟎𝟐𝟎 𝐇𝟏

𝟏 Element # Electrons

electron configuration

# Valence

electrons

Grade 10

trimester st1

4

Chemistry

Scientists tried to organize elements in a table,

Lavoisier He organized elements in four categories Gases, Metals, Nonmetals, and Earths.

Lavoisier's Table of Simple Substances

Metals Antimony Copper Silver Iron Arsenic Manganese Bismuth Tungsten Platina

Cobalt Tin Mercury Lead Molybdena Nickel Gold Zinc

Nonmetals Sulphur Phosph

orus

Pure

charcoal Radical boracique Radical muriatique Radical fluorique

Earths Chalk, calcareous

earth

Magnesia, base of

Epsom salt

Barote, or

heavy earth

Clay, earth of alum,

base of alum

Siliceous earth,

verifiable earth

Gases Light Heat Dephlogisticated

air Phlogisticated gas Inflammable air or gas

John Newlands' Octaves Newlands wanted to relate all the elements to each other.

Newlands arranged the known elements in a table by atomic

weights.

In doing so, he noticed some recurring patterns, and the

patterns were such that if he broke up his list of elements into

groups of seven, the first elements in each of those groups were

similar to one another, as was the second element in each group,

and the third, and so on. By analogy with the tonic musical scale

of seven notes, which form octaves, he called his discovery the

Law of Octaves

Meyer and Dmitri Mendeleev Mendeleev arranged the elements in a table

ordered by atomic mass.

In large part, the success of the Mendeleev's

analysis can be attributed to the gaps which he

predicted would contain undiscovered elements

with predictable properties.

Henry Moseley Mosley's research demonstrated that the ordering of elements in the table should be

according to atomic number not atomic weight.

PERIODIC LAW: The Periodic Law States That when elements are arranged in order

of increasing atomic number, there is a periodic repetition of their physical and chemical

properties.

Periodic table

Grade 10

trimester st1

5

Chemistry

Periods and Groups

Elements in the periodic table are arranged in periods (rows) and groups (columns).

Atomic number increases as you move across a period.

Metals Metals are located on the left side of the periodic

staircase on the periodic table. They are malleable,

ductile, good conductors of heat and electricity, solid

at room temperature (except for Mercury), and they

have a high luster (they are shiny). Metals make up

most of the elements in the periodic table.

Nonmetals Nonmetals are located on the right side of the

periodic staircase on the periodic table (except for

Hydrogen). They are brittle, not ductile, poor

conductors of heat and electricity, and they have a

low luster. Most are gases at room temperature, but

some are solids and Bromine is a liquid.

Metalloids Metalloids have properties of both metals and

nonmetals. A metalloid may behave as a metal under

some conditions, but the same metalloid may behave

as a nonmetal under other conditions.

Representative Elements The representative elements are found in groups 1 through 2 and groups 13 through 18 on

the periodic table.

13 14 15 16 17 A 3 A 4 A 5 A 6 7 A

18 A 8

A 1 2 A 2

Grade 10

trimester st1

6

Chemistry

Transition metals The transition metals are groups 3 through 12 in the middle of the periodic table

Inner transition metals The inner transition metals are found underneath the periodic table. The Lanthanide

series belongs in period 6 and the Actinide series belongs in period 7.

Label the following elements as a metal, nonmetal, or metalloid

Element Classification Element Classification Element Classification

C Nonmetal Pd metal Xe nonmetal

Mg metal H nonmetal Si metalloid

Bi metal Es metal O nonmetal

Na metal Ne nonmetal B metalloid

Circle the following element that is a metalloid

Argon Germanium Bismuth Zinc Hydrogen

Circle the following element that is not a transition metal

Osmium Titanium Gold Radon Copper

Circle all of the following elements that are representative elements

Sulfur Cerium Sodium Aluminum Iron

Circle the following element that is an inner transition metal

Nitrogen Hassium Californium Mercury Lithium

➢ There are ___18__ groups and __7___ periods in the periodic table.

➢ Chlorine has ___17__ valence electrons

➢ Groups 3 – 12 are called the __Transition___ metals.

➢ Write the symbol of the element that is in the 3rd period and group 13 ____Al_____

➢ Write the symbol of the element that is in the 5th period and group 11 ____Ag_____

Grade 10

trimester st1

7

Chemistry

Important Groups

Elements in a group share similar chemical and physical properties. There are groups of

elements in the periodic table that are given special names.

Alkali Metals (Li, Na, K, Rb, Cs, Fr)

✓ Alkali metals, excluding Hydrogen, are found in Group 1.

✓ They only have one valence electron in their outermost

energy.

✓ Only having one valence electron leads to alkali metals

being very unstable and highly reactive, meaning it is

likely to bond with other elements and lose its 1 valence

electron.

✓ They are all metals, extremely soft metals, which can be cut with a butter knife.

✓ Alkali metals are very abundant in nature.

✓ they have low densities and low melting and boiling points.

Alkaline Earth Metals (Be, Mg, Ca, Sr, Ba, Ra)

✓ Alkaline earth metals are found in Group 2.

✓ They have two valence electrons and very reactive,

likely to bond with other elements and lose 2 electrons.

✓ All the elements in the group bond similarly and there for

have similar properties.

Halogens (F, Cl, Br, I, At)

✓ Halogens are found in Group 17.

✓ They have seven valence electrons, so want to gain 1

more electron to make their outer energy level full.

✓ A halogen will easily bond with an alkali metal

(whom wants to lose 1 e-), together they form a salt.

Example NaCl (sodium chloride) is table salt.

Noble Gasses (He, Ne, Ar, Kr, Xe, Rn)

✓ Noble gasses are found in Group 18.

✓ They have eight valence electrons and are the most

stable of the elements (non‐reactive).

✓ Their outermost energy level or shell is full, so they do

not naturally bond with other elements.

✓ Noble gasses share properties like high densities, high

melting points, colorless, odorless, and tasteless.

H

Grade 10

trimester st1

8

Chemistry Lanthanide Series ✓ The lanthanide series include the “rare‐earth elements”

and are found on the top row of the inner transition metals.

✓ These elements are part of period 6.

✓ The lanthanide series get it name from the element

Lanthanum (La) atomic number 57 where the row would

fall after.

✓ All the elements in the lanthanide series have common

properties to the element Lanthanum.

Actinide Series ✓ The actinide series includes all radioactive metals and can

be found on the bottom row of the inner transition metals.

✓ These elements are part of period 7.

✓ The actinide series is named after the element Actinium

(Ac) atomic number 89 where the row would fall after.

✓ All the elements in the lanthanide series have common

properties to the element Actinium.

Locating an Element in periodic table

The location of the element in the periodic table depends on the number of protons. The

period can be deduced by the number of valence electrons. The number of electrons at the

outer level of any atom ranges between (1) and (8). The probability of the presence of the

element in the table is as follows:

# Valence electrons

(three) to (8 eight)(1 one) or (2)

Add 10 to the number of

electrons at the outer level

The same number of electrons of

the last level

Method of calculating

the group number

chlorine 𝐂𝐥𝟑𝟓𝟏𝟕

• Electronic config : 2,8,7

• # Valence electrons : 7

The element exists in group :17

Lithium 𝐋𝐢𝟕𝟑

• Electronic config 2,1

• # Valence electrons :1

• The element exists in group: 1

Example

Grade 10

trimester st1

9

Chemistry

Classification of elements: s-, p-, d-, f- Blocks

s-Block Elements

The elements of group 1 (alkali metals) and group 2 (alkaline earth metals) belong to the s-

block elements.

p-Block Elements

The p-Block Elements comprise those belonging to groups 13 to 18.

Representative Elements or Main Group Elements: The p-Block Elements together with

the s-block elements

The d-block Elements (Transition Elements)

These are the elements of group 3 to 12 in the center of the periodic table

The f-Block Elements (Inner-Transition elements)

The two rows of elements at the bottom of the periodic table, called the Lanthanoids

and Actinoids.

Grade 10

trimester st1

10

Chemistry

Use the following words to match up to the descriptions below.

Representative Elements Transition Metals Inner Transition Metals

Periods Groups Lanthanide Series Actinide Series Metals

Metalloids Non-metals Alkali Metals Alkaline Earth Metals

Halogens Noble Gases

Actinide Series all elements in this series are radioactive

Non-metals poor conductors of heat& electricity; solids are dull & brittle

Representative Elements made up of groups 1,2, & 13-­‐18

Groups vertical columns on the periodic table; all elements have similar

chemical & physical properties; all elements have the same number of valence electrons

Representative Elements The p-Block Elements together with the s-block elements

Inner Transition Metals made up of the Lanthanide series and the Actinide series

Noble Gases do not naturally combine with other elements

Metals are ductile, malleable and lustrous

Alkaline Earth Metals all elements of this group have 2 valence electrons

Transition Metals made up of groups 3-­‐12

Halogens elements in this group easily bond with an alkali metal to form a salt.

Lanthanide Series the “Rare Earths Elements”

Periods horizontal rows, atomic number increases as you move across the row

Alkali Metals all elements in this group have 1 valence electron

Metalloids have the properties of both metals & non‐metals

Nonmetal Nitrogen Noble gas Radon

Inner Transition Metal Uranium Alkali Metal Rubidium

Transition Metal Silver Alkali Earth Metal Radium

Halogen Bromine Alkali Earth Metal Calcium

Alkali Metal Lithium Nonmetal Sulfur

Halogen Iodine Transition Metal Lead

Noble gas Neon Metal Bismuth

Metalloids Silicon Metalloids Antimony

Grade 10

trimester st1

11

Chemistry

Write the suitable answer beside the following,

1) ____Cr______ Transition Metal number 24

2) _____I_____ A common solid halogen

3) _____Boron_____ Family 13 bears this name

4) _____Ba_____ An active alkaline earth metal with 56 protons

5) _____Na_____ The alkali metal of period 3

6) ______Na____ The metal element that makes up table salt

7) _____Li_____ The first of the alkali metals

8) _____O_____ The first element of family 16

9) _____P_____ A period 2 nonmetal with 5 valence electrons

10) _____Ga_____ Element with atomic number 31

11) _____Ra_____ The last of the alkaline earth metals

12) _____Ge_____ Mendeleev predicted the existence of this metalloid

13) _____Th_____ The first element in the actinide series

14) _____O_____ Period 2 nonmetal with 6 valence electrons

15) _____Rn_____ The last of the noble gases

16) ____Tungesten______ A transition metal used in incandescent light bulbs.

17) _____As_____ Period 4, Group 15 element

18) _____P_____ The second element in Group 15

19) _____S_____ Period 3 element with 6 valence electrons.

20) _____C_____ This element is in the same family as lead and it has fewer protons

than sodium.

21) ____Au______ This element has an atomic number that is one greater than platinum.

22) ____Bi______ This element has the most protons of any element in group 15.

23) ____I______ This element has the more than 50 but less than 75 protons and it is in

group 17.

24) _____Ca_____ This group 2 element has fewer protons than bromine, but more

protons than sulfur.

25) _____O_____ This element has the lowest atomic number of any group 16 element.

Grade 10

trimester st1

12

Chemistry

26) _____Ni_____ This element has an atomic number that is double the atomic number

of silicon.

27) _____Cl_____ This element has more valence electrons than oxygen, fewer valence

electrons than neon, more protons than sodium, but fewer protons than argon.

28) _____N_____ This element has an atomic number lower than that of aluminum and

one less valence electron than the group 16 elements.

29) _____K_____ This element is in group 1 and has a high atomic number than

chlorine, but a lower atomic number than bromine.

30) ______Ba____ Which element is a metal: Ba or At ?

31) _____4_____ Which period is Ca in ?

32) _____15_____ What is the number of the group N is in ?

33) ______Rb____ Which element is an alkali metal: Rb or Al ?

34) _____Na_____ Which element is a halogen: Na or Cl ?

35) _____Ne_____ Which element is a noble gas: Ne or Br or O ?

36) _____Sr_____ Which element would be a positive ion in a compound: Sr or Te ?

37) _____5_____ How many electron dots should As have ?

38) ______P____ Which element has 5 valence electrons? B or P ?

39) ______Ar____ Which element has 18 electrons ?

40) _____45_____ How many neutrons does bromine-80 have?

On the line to the right identify the element’s family if it belongs to one of the families

listed below, otherwise leave the line blank.

Metals - Alkali Metal - Halogen - Nonmetals - Group 2 Metal

Noble gas - Metalloids - Transition Metal

Metals Potassium Group 2 Metal Magnesium Metalloids Germanium

Nonmetals Sulfur Transition

Metal Gold Halogen Fluorine

Metalloids Antimony Noble gas Krypton Alkali Metal Cesium

Halogen Iodine Halogen Bromine Transition

Metal Titanium

Grade 10

trimester st1

13

Chemistry

Which one of the following pairs of elements is the most metallic?

1. _______ a) potassium b) bromine

2. _______ a) cesium b) sodium

3. _______ a) silicon b) aluminum

4. _______ a) gold b) bismuth

Two elements X and Y have the following properties.

Element X Element Y

Metallic luster

Two valence electrons

period thLocated in the 4

Without metallic luster

Four valence electrons

6 protons

1. Which symbols from the periodic table correspond to elements X and Y respectively?

A) Ca and C B) K and B C) K and C D) Ca and B

2. Which of the following statements about the properties of metals is correct?

A) They are ductile but are not shiny.

B) They conduct electricity but are not ductile.

C) They do not conduct electricity and are not shiny.

D) They conduct electricity and heat and are opaque.

Four elements from the periodic table are described below.

Element A: This metal reacts vigorously with water and its electrons are distributed among

three energy levels.

Element B: This nonmetal is located in Period 3 and used to disinfect or to kill bacteria in

pools.

Element C: Its electron configuration is pictured in the Bohr model to the

right

Element D: Its outermost energy level is full and it could have 22 neutrons.

Complete the table by indicating the symbol and the name of the chemical family for each

of these elements.

Element Chemical Symbol Chemical Family Name Block

Element A Na Alkali metals s

Element B Cl Halogenes p

Element C Mg Alkaline Earth metals s

Element D Ar Nobel Gases p

Grade 10

trimester st1

14

Chemistry

The following diagram represents the Bohr model of an element.

1. Which of the following is true?

a) The element is located in period 1 and is a Group II Metal

b) The element is located in period 1 and is an alkali metal.

c) The element is located in period 2 and is an alkali metal.

d) The element is located in period 2 and is a halogen

2. Which of the following states two properties of the elements in the halogen family?

a) They are soft metals and highly reactive.

b) They do not conduct electricity and are not shiny.

c) They conduct electricity but are less reactive than alkali metals.

d) They are colorless in their natural state and are not chemically reactive

An element has the following characteristics:

• It has a metallic luster.

• It conducts electricity.

• It has 3 valence electrons.

• It is a metal.

•

What is this element?

A) Aluminum B) Lithium C) Silicon D) Sodium

The following diagram represents the Bohr atomic model for an element in the periodic

table.

Which of the following is a correct statement about this element?

A) It is an alkali metal that has 19 protons and is located in Period 4.

B) It is a nonmetal that is not very reactive and that has 19 protons and 1 valence

electron.

C) It is a halogen that has 19 electrons and is located in Period 1.

D) It is a highly reactive metal that has 20 protons.

Grade 10

trimester st1

15

Chemistry

Complete the following.

Block Period# Energy

levelsGroup

# Valence Electrons

Electron config.

Element

s 221882,8𝐍𝐞𝟐𝟎𝟏𝟎

p44222,8,8,2𝐂𝐚𝟒𝟎𝟐𝟎

s11111𝐇𝟏𝟏

s22222,2𝐁𝐞𝟗𝟒

p331332,8,3𝐀𝐥𝟐𝟕𝟏𝟑

p221772,7𝐅𝟏𝟖𝟗

p221662,6𝐎𝟏𝟔𝟖

s331222,8,2𝐌𝐠𝟐𝟒𝟏𝟐

p221552,5𝐍𝟏𝟓𝟕

p221242,4𝐂𝟏𝟐𝟔

p111822𝐇𝐞𝟒𝟐

Grade 10

trimester st1

16

Chemistry